Watch.



A. PPISTBR.

WATCH. APPLICATION'PILED 211.12, 1907.

Patented May 25, 1909.

THE No'Rms FUER: ro., wAsNmcToN. 1:.c.

ALFRED PFISTER, OF ST. IMIER, SWITZERLAND, ASSIGNOR TO FABRIQUE DESLONGINES FRANOILLON & OIE., OF ST. IMIER, SWITZERLAND.

WATCH.

To all whom it may concern:

Be it known that i, ALFRED Pris'rnn, citizen of Switzerland, residing atSt, Imier, Canton de Berne, Switzerland, have invented certain new anduseful improvements in W atches, and l do hereby declare the followingto be a full, clear, and exact description of the invention, such aswill enable others skilled in the art to which it appertains to malreand use the same.

My invention relates to improvements in watches and particularly to thespring motor mechanism of a watch.

The object of the invention is to provide a simple and eHicientconstruction of the barrel whereby all lateral strain on the arbor willbe avoided and at the same time overwinding is prevented.

My invention consists in the features, details of construction, andcombination of parts which will first be described in connection withthe accompanying drawings and then particularly pointed out in theclaims.

In the drawings l have shown a sectional view of a spring motormechanism embodyf ing my invention.

Referring to the drawings, I) is the drum of a barrel fixed to the arbora to which is secured a hub c provided with a hook c to which the innerend of the main spring is attached. About the arbor a is loosely mounteda spur wheel d which meshes with a winding wheel f. To the spur wheel d/is secured the lid or cover e which is rotatable within the drum of thebarrel and is provided on its inner wall with a hook g to which theouter end of the spring is attached. rThe cover e and the spur wheel dare secured together by a clamping nut or collar d2 mounted on the largecentral threaded hub of the spur wheel and bearing against the cover.The hub of the spur wheel is journaled upon a. dowel 7L of suitablematerial, such as cast steel, which is iiXed in a recess in the upperplate t2, as clearly shown. This construction prevents the transmissionfrom the spur wheel to the Specification o Letters Patent.

Application led April l2, 1907.

Patented May 25, 1909.

Serial No. 367,735.

l arbor of any lateral pressure or strain due to the action of thespring on the cover and the spur wheel.

The 'winding wheel f is of the usual construction arranged to be rotatedto wind the watch but prevented from turning backward by the usual pawland ratchet wheel.

The drum b has around its periphery the usual great wheel, as indicatedat b, whereby it may drive the train.

During the ruiming of the watch, the spurwheel d and the cover or lid cof the barrel are held stationary by the pawl and ratchet wheelhereinbefore mentioned, while the drum l) turns under the action oi' thespring and drives the train, the arbor rotating with the drum.

Having thus fully described my invention, what l claim is l. in a watch,the combination with a drum and a cover, said drum and cover beingrelatively movable, of an arbor on which the drum is mounted, a springconnected to the cover and arranged to drive the drum, a spur-wheelconnected to the cover and provided with a central opening, means forrotating the spur-wheel to wind the spring, and a dowel surrounding thearbor and projecting into the central opening of the spurewheel.

2. In a watch, the combination with a drum and a cover, said drum andcover being relatively movable, of an arbor on which the drum ismounted, a spring within the cover and drum, said spring having one endconnected to the cover and the other to the arbor, a spur-wheel providedwith an enlarged central hub proj ecting inside the cover, a clampingnut on said hub inside the cover, and a dowel surrounding the arbor andextending into the central hub oi the spur-wheel.

ln testimony whereof l hereunto affix my signature in the presence oftwo witnesses.

ALFRED PFTSTER. l.Witnesses FRIEDRICH Nassau, NATHANIEL LEUBA.

